RPA Southern Pilot Search of 107 Stars

DOI

The recent detection of a binary neutron star merger and the clear evidence for the decay of radioactive material observed in this event have, after 60 years of effort, provided an astrophysical site for the rapid neutron- capture (r-) process which is responsible for the production of the heaviest elements in our universe. However, observations of metal-poor stars with highly-enhanced r-process elements have revealed abundance patterns suggesting that multiple sites may be involved. To address this issue and to advance our understanding of the r-process, we have initiated an extensive search for bright (V<13.5), very metal-poor ([Fe/H]<-2) stars in the Milky Way halo exhibiting strongly-enhanced r-process signatures. This paper presents the first sample collected in the southern hemisphere using the echelle spectrograph on du Pont 2.5m telescope at Las Campanas Observatory. We have observed and analyzed 107 stars with -3.13<[Fe/H]<-0.79. Of those, 12 stars are strongly enhanced in heavy r-process elements (r-II), 42 stars show moderate enhancements of heavy r-process material (r-I), and 20 stars exhibit low abundances of the heavy r-process elements and higher abundances of the light r-process elements relative to the heavy ones (limited-r). This search is more successful at finding r- process-enhanced stars compared to previous searches, primarily due to a refined target-selection procedure.

Cone search capability for table J/ApJ/858/92/stars (Stellar parameters and abundances (tables 4 and 5))

Cone search capability for table J/ApJ/858/92/table2 (Observation log for the 107 stars)

Identifier
DOI http://doi.org/10.26093/cds/vizier.18580092
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/ApJ/858/92
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/858/92
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/858/92
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/ApJ/858/92
Provenance
Creator Hansen T.T.; Holmbeck E.M.; Beers T.C.; Placco V.M.; Roederer I.U.,Frebel A.; Sakari C.M.; Simon J.D.; Thompson I.B.
Publisher CDS
Publication Year 2018
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Interdisciplinary Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy